/*
 * Copyright (C) 2014-present, Wei Chou (weichou2010@gmail.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.wei.c.widget.text;

import android.text.InputFilter;
import android.text.Spanned;

/**
 * @author 周伟 Wei Chou(weichou2010@gmail.com)
 */
public class RegexFilter implements InputFilter {
	private final String mRegex;
	public RegexFilter(String regex) {
		mRegex = regex;
	}

	@Override
	public CharSequence filter(CharSequence source, int start, int end,
			Spanned dest, int dstart, int dend) {
		String s = new StringBuffer(dest).replace(dstart, dend,
				source.subSequence(start, end).toString()).toString();
		if(!s.matches(mRegex)) {
			return "";
		}
		return null;
	}
}
